The present invention relates to a reversible, radial-piston hydraulic motor driven by oil or a less viscous fluid in which propulsion is the product of fluid distribution into pistons disposed radially with respect to a motor shaft.
Reversible radial motors are known in which a crankshaft coupling between an individual cylinder (or piston) and shaft is obtained by means of a shoe of quasi-spherical profile, held tight to a motor shaft pivot by means of a pair of lateral rings, while the coupling between the individual piston (or cylinder) and motor at a peripheral location is rigid, or perhaps achieved by means of a gudgeon. Current techniques have also produced axial-flow pumps in which semispherical couplings are utilised in uniting the `big-end` of each individual piston connecting-rod with the pump main rotating body.
The above techniques are susceptible to further improvement with regard to the following requirements: avoidance of grinding of the shoe with the shaft pivot thereby diminishing friction; elimination of eccentric weight thereby obtaining greater speeds; absence of transverse stress on cylinder/piston coupling parts and other related support components, gaining a tighter fluid seal; simplification of fluid distribution by shortening of ducts; a more simple device by means of which to vary the cubic capacity of the motor; utilization of more economical, synthetic fluids--or emulsified water, in place of oil, these being less of a pollution hazard, and either less inflammable or totally non-flammable.
It is accordingly an object of the present invention to provide a radial hydraulic motor free of eccentric weight, with a reduced degree of friction, without transverse stress on cylinder and piston couplings, and which may be run on synthetic fluids or emulsified water, and having means for varying the cubic capacity of the motor itself.